Abstract:
A compass output in a first portable electronic device is monitored as the first device and a second electronic device come closer to each other. It is determined, by a process running in the first device, whether a magnetic field signature that is based on the monitored compass output is associated with a previously defined type of electronic device with which a network device discovery process is to be conducted. Other embodiments are also described and claimed.
Abstract:
A power-management unit is described. This power-management unit allows a common signal line to communicate data between an integrated circuit (which may be external to the power-management unit) and a battery-monitoring mechanism in a battery pack, and to convey a signal that represents a temperature state of the battery pack to a temperature-monitoring circuit or mechanism that monitors the temperature state of the battery pack. In particular, the power-management unit may include a single-wire interface or a multiplexer that, at a given time, selectively couples the signal line from the battery pack either to the integrated circuit or the temperature-monitoring circuit based on a control signal provided by the integrated circuit (for example, via an I2C bus or interface). In this way, the power-management unit may reduce the number of signal lines needed to communicate with the battery-monitoring mechanism and to convey the signal.
Abstract:
An accessory strobe device for a mobile device may operate to provide illumination at the same time as an internal built-in strobe (flash) of the mobile device. The accessory strobe device may receive a single, unidirectional signal from the mobile device that provides signals related to the timing of the internal strobe. The accessory strobe device may process the received signal to control its illumination using the timing and relative intensity levels of the internal strobe during metering and main (normal) flash operations associated with a camera on the mobile device. With the accessory strobe device operating using timing and relative intensity levels in a predetermined relationship with the timing and relative intensity levels of the internal strobe, the accessory strobe device may be used to complement the internal strobe during the metering and main (normal) flash operations for the camera.
Abstract:
Power supply topologies can leverage relatively smaller component sizes while meeting the power requirements of loads. In a first stage, a determination is made as to whether a high current limit is exceeded for a first duration, or whether an average current provided exceeds an average current limit, such that a power supply component (e.g., inductor) is thermally stressed. In either event, a clock frequency is reduced by a first factor. In a second stage, a determination is made as to whether an output voltage drops below a voltage threshold. If so, the clock frequency may be further reduced by a second factor.
Abstract:
Systems and methods for in-band communication across a wireless power interface from a load device to a source device. The load device selectively modifies the timing of switches within a voltage rectifier coupled to an output of a receive coil within the load device that receives power from a transmit coil within the source device. The source device detects changes in the power transfer (or in the relative timing of a voltage or a current) as digital information received from the load device.
Abstract:
A multi-phase switch mode, voltage regulator has a transient mode portion in which a phase control output is coupled to one or more control inputs of one or more switch circuits that conduct inductor current through one or more transient phase inductors, from amongst a number of phase inductors. A slew mode control circuit detects a high slope and then a low slope in the feedback voltage and, in between detection of the high slope and the low slope, pulses the phase control output of the transient mode portion so that the switch circuit that conducts transient phase inductor current adds power to, or sinks power from, the power supply output. Other embodiments are also described.
Abstract:
Systems and methods for in-band communication across a wireless power interface from a load device to a source device. The load device selectively modifies the timing of switches within a voltage rectifier coupled to an output of a receive coil within the load device that receives power from a transmit coil within the source device. The source device detects changes in the power transfer (or in the relative timing of a voltage or a current) as digital information received from the load device.
Abstract:
Methods, circuits, and apparatus to distribute power among devices in an electronic system where a device may receive power from more than one source, may have a bidirectional power connector, or both. One example may resolve conflicts when an electronic device receives power from more than one source. In this example, the device may determine which source may provide the most power, and may select to receive power from the power source that may deliver the most power. Other examples may have a preference to receive power from a particular source or via a specific connector. Other examples may switch from receiving power over a first connector to providing power over the first connector, while others may receive and provide power over different connectors at the same time. Another may be connected to a battery, and may draw power from the battery or not depending on the type of battery.
Abstract:
An asymmetric multiphase boost that provides flash functionality for display backlights. A backlight power management module for a display backlight may implement and control an asymmetric multiphase boost that includes two boost phases: a primary boost phase for typical display backlighting, and a secondary or flash boost phase that provides flash functionality via the display backlight when needed. The primary boost phase may be sized to provide high low-load efficiency, high inductance, and low switching frequency for normal display backlight operations. The flash boost phase may be sized for high current and peak power, low inductance, and high switching frequency for pulsed current applications. Via the asymmetric multiphase boost, the backlight power management module may, for example, be used to provide a camera flash function for front facing cameras.
Abstract:
A device to capture an image includes a camera oriented to capture a first image of a subject and a display oriented to display a second image that is viewable by the subject. A backlight is coupled to the display to provide light that passes through the display toward the subject. An image processor is coupled to the camera and the backlight to adjust an amount of light provided by the backlight responsive to a quality of the first image. The light provided by the backlight may illuminate the subject and thereby improve the quality of the first image. The image processor may further adjust the amount of light provided by the backlight responsive to an ambient light level sensed by an ambient light sensor. The image processor may further adjust the second image to adjust an amount of light that passes through the display.